#include <contents.h>

Inheritance diagram for impeller::Contents:

Classes
struct	SnapshotOptions

Public Types
using	ColorFilterProc = std::function< Color(Color)>

using	RenderProc = std::function< bool(const ContentContext &renderer, const Entity &entity, RenderPass &pass)>

using	CoverageProc = std::function< std::optional< Rect >(const Entity &entity)>

Public Member Functions
	Contents ()

virtual	~Contents ()

virtual bool	Render (const ContentContext &renderer, const Entity &entity, RenderPass &pass) const =0

virtual std::optional< Rect >	GetCoverage (const Entity &entity) const =0
	Get the area of the render pass that will be affected when this contents is rendered.

void	SetCoverageHint (std::optional< Rect > coverage_hint)
	Hint that specifies the coverage area of this Contents that will actually be used during rendering. This is for optimization purposes only and can not be relied on as a clip. May optionally affect the result of `GetCoverage()`.

const std::optional< Rect > &	GetCoverageHint () const

virtual bool	IsOpaque (const Matrix &transform) const
	Whether this Contents only emits opaque source colors from the fragment stage. This value does not account for any entity properties (e.g. the blend mode), clips/visibility culling, or inherited opacity.

virtual std::optional< Snapshot >	RenderToSnapshot (const ContentContext &renderer, const Entity &entity, const SnapshotOptions &options) const
	Render this contents to a snapshot, respecting the entity's transform, path, clip depth, and blend mode. The result texture size is always the size of `GetCoverage(entity)`.

std::optional< Size >	GetColorSourceSize () const
	Return the color source's intrinsic size, if available.

void	SetColorSourceSize (Size size)

virtual void	SetInheritedOpacity (Scalar opacity)
	Inherit the provided opacity.

virtual std::optional< Color >	AsBackgroundColor (const Entity &entity, ISize target_size) const
	Returns a color if this Contents will flood the given `target_size` with a color. This output color is the "Source" color that will be used for the Entity's blend operation.

virtual bool	ApplyColorFilter (const ColorFilterProc &color_filter_proc)
	If possible, applies a color filter to this contents inputs on the CPU.

Static Public Member Functions
static std::shared_ptr< Contents >	MakeAnonymous (RenderProc render_proc, CoverageProc coverage_proc)

Detailed Description

Definition at line 31 of file contents.h.

Member Typedef Documentation

◆ ColorFilterProc

using impeller::Contents::ColorFilterProc = std::function<Color(Color)>

A procedure that filters a given unpremultiplied color to produce a new unpremultiplied color.

Definition at line 35 of file contents.h.

◆ CoverageProc

using impeller::Contents::CoverageProc = std::function<std::optional<Rect>(const Entity& entity)>

Definition at line 40 of file contents.h.

◆ RenderProc

using impeller::Contents::RenderProc = std::function<bool(const ContentContext& renderer, const Entity& entity, RenderPass& pass)>

Definition at line 37 of file contents.h.

Constructor & Destructor Documentation

◆ Contents()

impeller::Contents::Contents ( )

default

◆ ~Contents()

impeller::Contents::~Contents ( )

virtualdefault

Member Function Documentation

◆ ApplyColorFilter()

bool impeller::Contents::ApplyColorFilter ( const ColorFilterProc & color_filter_proc )

virtual

If possible, applies a color filter to this contents inputs on the CPU.

This method will either fully apply the color filter or perform no action. Partial/incorrect application of the color filter will never occur.

Parameters

[in] color_filter_proc A function that filters a given unpremultiplied color to produce a new unpremultiplied color.

Returns: True if the color filter was able to be fully applied to all all relevant inputs. Otherwise, this operation is a no-op and false is returned.

Reimplemented in impeller::ConicalGradientContents, impeller::LinearGradientContents, impeller::RadialGradientContents, impeller::SolidColorContents, impeller::SolidRRectLikeBlurContents, and impeller::SweepGradientContents.

Definition at line 128 of file contents.cc.

                                                      {
  return false;
}

◆ AsBackgroundColor()

std::optional< Color > impeller::Contents::AsBackgroundColor	(	const Entity &	entity,
		ISize	target_size
	)		const

virtual

Returns a color if this Contents will flood the given target_size with a color. This output color is the "Source" color that will be used for the Entity's blend operation.

This is useful for absorbing full screen solid color draws into subpass clear colors.

Reimplemented in impeller::SolidColorContents.

Definition at line 123 of file contents.cc.

                                                                          {
  return {};
}

◆ GetColorSourceSize()

std::optional< Size > impeller::Contents::GetColorSourceSize ( ) const

Return the color source's intrinsic size, if available.

    For example, a gradient has a size based on its end and beginning
    points, ignoring any tiling. Solid colors and runtime effects have
    no size.

Definition at line 141 of file contents.cc.

                                                     {
  return color_source_size_;
};

◆ GetCoverage()

virtual std::optional< Rect > impeller::Contents::GetCoverage ( const Entity & entity ) const

pure virtual

Get the area of the render pass that will be affected when this contents is rendered.

During rendering, coverage coordinates count pixels from the top left corner of the framebuffer.

Returns: The coverage rectangle. An std::nullopt result means that rendering this contents has no effect on the output color.

Implemented in impeller::AnonymousContents, impeller::AtlasContents, impeller::ColorFilterAtlasContents, impeller::CircleContents, impeller::ColorSourceContents, impeller::FilterContents, impeller::LineContents, impeller::SolidColorContents, impeller::SolidRRectLikeBlurContents, impeller::TextContents, impeller::TextureContents, and impeller::VerticesSimpleBlendContents.

Referenced by impeller::ColorSourceContents::DrawGeometry(), and RenderToSnapshot().

◆ GetCoverageHint()

const std::optional< Rect > & impeller::Contents::GetCoverageHint ( ) const

Definition at line 137 of file contents.cc.

                                                         {
  return coverage_hint_;
}

Referenced by impeller::FilterContents::Render().

◆ IsOpaque()

bool impeller::Contents::IsOpaque ( const Matrix & transform ) const

virtual

Whether this Contents only emits opaque source colors from the fragment stage. This value does not account for any entity properties (e.g. the blend mode), clips/visibility culling, or inherited opacity.

Parameters

transform The current transform matrix of the entity that will render this contents.

Reimplemented in impeller::LinearGradientContents, impeller::RadialGradientContents, impeller::SolidColorContents, impeller::SweepGradientContents, and impeller::TiledTextureContents.

Definition at line 52 of file contents.cc.

                                                     {
  return false;
}

Referenced by impeller::testing::TEST_P().

◆ MakeAnonymous()

std::shared_ptr< Contents > impeller::Contents::MakeAnonymous	(	Contents::RenderProc	render_proc,
		Contents::CoverageProc	coverage_proc
	)

static

Definition at line 41 of file contents.cc.

                                        {
  return AnonymousContents::Make(std::move(render_proc),
                                 std::move(coverage_proc));
}

References impeller::AnonymousContents::Make().

◆ Render()

virtual bool impeller::Contents::Render	(	const ContentContext &	renderer,
		const Entity &	entity,
		RenderPass &	pass
	)		const

pure virtual

◆ RenderToSnapshot()

std::optional< Snapshot > impeller::Contents::RenderToSnapshot	(	const ContentContext &	renderer,
		const Entity &	entity,
		const SnapshotOptions &	options
	)		const

virtual

Render this contents to a snapshot, respecting the entity's transform, path, clip depth, and blend mode. The result texture size is always the size of GetCoverage(entity).

Reimplemented in impeller::FilterContents, impeller::TextureContents, and impeller::TiledTextureContents.

Definition at line 56 of file contents.cc.

                                                  {
  auto coverage = GetCoverage(entity);
  if (!coverage.has_value()) {
    return std::nullopt;
  }
 
  std::shared_ptr<CommandBuffer> command_buffer =
      renderer.GetContext()->CreateCommandBuffer();
  if (!command_buffer) {
    return std::nullopt;
  }
 
  // Pad Contents snapshots with 1 pixel borders to ensure correct sampling
  // behavior. Not doing so results in a coverage leak for filters that support
  // customizing the input sampling mode. Snapshots of contents should be
  // theoretically treated as infinite size just like layers.
  coverage = coverage->Expand(options.coverage_expansion);
 
  if (options.coverage_limit.has_value()) {
    coverage = coverage->Intersection(*options.coverage_limit);
    if (!coverage.has_value()) {
      return std::nullopt;
    }
  }
 
  ISize subpass_size = ISize::Ceil(coverage->GetSize());
  fml::StatusOr<RenderTarget> render_target = renderer.MakeSubpass(
      options.label, subpass_size, command_buffer,
      [&contents = *this, &entity, &coverage](const ContentContext& renderer,
                                              RenderPass& pass) -> bool {
        Entity sub_entity;
        sub_entity.SetBlendMode(BlendMode::kSrcOver);
        sub_entity.SetTransform(
            Matrix::MakeTranslation(Vector3(-coverage->GetOrigin())) *
            entity.GetTransform());
        return contents.Render(renderer, sub_entity, pass);
      },
      options.msaa_enabled, /*depth_stencil_enabled=*/true,
      std::min(options.mip_count,
               static_cast<int32_t>(subpass_size.MipCount())));
 
  if (!render_target.ok()) {
    return std::nullopt;
  }
  if (!renderer.GetContext()->EnqueueCommandBuffer(std::move(command_buffer))) {
    return std::nullopt;
  }
 
  auto snapshot = Snapshot{
      .texture = render_target.value().GetRenderTargetTexture(),
      .transform = Matrix::MakeTranslation(coverage->GetOrigin()),
  };
  if (options.sampler_descriptor.has_value()) {
    snapshot.sampler_descriptor = options.sampler_descriptor.value();
  }
 
  return snapshot;
}

References impeller::TSize< T >::Ceil(), impeller::Contents::SnapshotOptions::coverage_expansion, impeller::Contents::SnapshotOptions::coverage_limit, impeller::ContentContext::GetContext(), GetCoverage(), impeller::Contents::SnapshotOptions::label, impeller::ContentContext::MakeSubpass(), impeller::Matrix::MakeTranslation(), impeller::Contents::SnapshotOptions::mip_count, impeller::Contents::SnapshotOptions::msaa_enabled, fml::StatusOr< T >::ok(), impeller::Contents::SnapshotOptions::sampler_descriptor, subpass_size, impeller::Snapshot::texture, and fml::StatusOr< T >::value().

Referenced by impeller::TextureContents::RenderToSnapshot(), and impeller::TiledTextureContents::RenderToSnapshot().

◆ SetColorSourceSize()

void impeller::Contents::SetColorSourceSize ( Size size )

Definition at line 145 of file contents.cc.

                                           {
  color_source_size_ = size;
}

◆ SetCoverageHint()

void impeller::Contents::SetCoverageHint ( std::optional< Rect > coverage_hint )

Hint that specifies the coverage area of this Contents that will actually be used during rendering. This is for optimization purposes only and can not be relied on as a clip. May optionally affect the result of GetCoverage().

Definition at line 133 of file contents.cc.

                                                              {
  coverage_hint_ = coverage_hint;
}

◆ SetInheritedOpacity()

void impeller::Contents::SetInheritedOpacity ( Scalar opacity )

virtual

Inherit the provided opacity.

   Use of this method is invalid if CanAcceptOpacity returns false.

Reimplemented in impeller::ColorSourceContents, impeller::ColorFilterContents, impeller::TextContents, and impeller::TextureContents.

Definition at line 118 of file contents.cc.

                                                 {
  VALIDATION_LOG << "Contents::SetInheritedOpacity should never be called when "
                    "Contents::CanAcceptOpacity returns false.";
}

References VALIDATION_LOG.

The documentation for this class was generated from the following files:

impeller/entity/contents/contents.h
impeller/entity/contents/contents.cc

Classes

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

◆ ColorFilterProc

◆ CoverageProc

◆ RenderProc

Constructor & Destructor Documentation

◆ Contents()

◆ ~Contents()

Member Function Documentation

◆ ApplyColorFilter()

◆ AsBackgroundColor()

◆ GetColorSourceSize()

◆ GetCoverage()

◆ GetCoverageHint()

◆ IsOpaque()

◆ MakeAnonymous()

◆ Render()

◆ RenderToSnapshot()

◆ SetColorSourceSize()

◆ SetCoverageHint()

◆ SetInheritedOpacity()